1. Field of the Invention
Embodiments of the present invention generally relate to a method of manufacturing a semiconductor device. More particularly, the invention is directed to a method of thermally processing a substrate.
2. Description of the Related Art
The integrated circuit (IC) market is continually demanding greater memory capacity, faster switching speeds, and smaller feature sizes. One of the major steps the industry has taken to address these demands is to change from batch processing silicon wafers in large furnaces to single wafer processing in a small chamber. During such single wafer processing the wafer is typically heated to high temperatures so that various chemical and physical reactions can take place in multiple IC devices defined in the wafer.
Integrated circuit can be fabricated relative to one or both of bulk semiconductor substrates, such as silicon wafers, and silicon-on-insulator (SOI) substrates. One method of forming SOI substrate includes epitaxially growing single crystalline silicon on insulator. Epitaxial silicon single crystal wafers have long been widely used as wafers for the manufacture of discrete semiconductors, bipolar ICs and so forth because of their excellent characteristics. Epitaxial silicon single crystal wafers are also widely used for microprocessor units or flash memory devices because of their excellent soft error and latch up characteristics. Unfortunately, epitaxially grown silicon tends to form crystalline defects such as dislocations and stacking faults, which can result in undesired leakage within or between the resulting fabricated devices. In addition, epitaxial growth techniques have a very slow growth rate since it requires close lattice matching between the substrate and the overlayer, which therefore significantly reduces throughput and causes higher operating cost.
Therefore, there exists a need for improved methods that can be used to efficiently form a high quality single crystal layer over a substrate.